Deprecate (T)Pythia6

The Pythia6 generator interface and use of Pythia6Decayer
is deprecated following the decision of ROOT to take the same
step (https://root.cern/doc/v630/release-notes.html)

In any case, Pythia6 was no longer actively used in the code
and we now use Pythia8 as a complete replacement.

Fixes https://alice.its.cern.ch/jira/browse/O2-4542

Author: sawenzel

Detectors/gconfig/CMakeLists.txt

@@ -16,12 +16,12 @@ o2_add_library(G3Setup
 
 o2_add_library(G4Setup
                SOURCES src/G4Config.cxx
-               PUBLIC_LINK_LIBRARIES MC::Geant4VMC MC::Geant4 FairRoot::Base O2::SimulationDataFormat O2::Generators O2::SimSetup  ROOT::EGPythia6
+               PUBLIC_LINK_LIBRARIES MC::Geant4VMC MC::Geant4 FairRoot::Base O2::SimulationDataFormat O2::Generators O2::SimSetup
 )
 
 o2_add_library(FLUKASetup
                SOURCES src/FlukaConfig.cxx
-               PUBLIC_LINK_LIBRARIES FairRoot::Base O2::SimulationDataFormat O2::Generators ROOT::EGPythia6 O2::SimSetup
+               PUBLIC_LINK_LIBRARIES FairRoot::Base O2::SimulationDataFormat O2::Generators O2::SimSetup
 )
 
 o2_add_library(MCReplaySetup
@@ -44,9 +44,6 @@ o2_target_root_dictionary(SimSetup
                                   include/SimSetup/FlukaParam.h
                                   include/SimSetup/MCReplayParam.h
                           LINKDEF src/GConfLinkDef.h)
-o2_add_test_root_macro(DecayConfig.C
-                       PUBLIC_LINK_LIBRARIES O2::SimSetup
-                       LABELS simsetup)
 
 o2_add_test_root_macro(UserDecay.C
                        PUBLIC_LINK_LIBRARIES O2::SimSetup

Detectors/gconfig/DecayConfig.C

@@ -16,7 +16,6 @@
 #include <fairlogger/Logger.h>
 #include "TGeant4.h"
 #include "TG4RunConfiguration.h"
-#include "TPythia6Decayer.h"
 #include "FairModule.h"
 #include "SimConfig/G4Params.h"
 #include "SimConfig/SimParams.h"

Detectors/gconfig/src/G4Config.cxx

@@ -9,10 +9,6 @@
 # granted to it by virtue of its status as an Intergovernmental Organization
 # or submit itself to any jurisdiction.
 
-if(pythia6_FOUND)
-  set(pythia6Target ROOT::EGPythia6 MC::Pythia6)
-endif()
-
 if(pythia_FOUND)
   set(pythiaTarget MC::Pythia)
 endif()
@@ -43,8 +39,6 @@ o2_add_library(Generators
                        src/GeneratorTParticle.cxx
                        src/GeneratorTParticleParam.cxx
                        src/GeneratorService.cxx
-                       $<$<BOOL:${pythia6_FOUND}>:src/GeneratorPythia6.cxx>
-                       $<$<BOOL:${pythia6_FOUND}>:src/GeneratorPythia6Param.cxx>
                        $<$<BOOL:${pythia_FOUND}>:src/GeneratorPythia8.cxx>
                        $<$<BOOL:${pythia_FOUND}>:src/DecayerPythia8.cxx>
                        $<$<BOOL:${pythia_FOUND}>:src/GeneratorPythia8Param.cxx>
@@ -53,14 +47,10 @@ o2_add_library(Generators
                        $<$<BOOL:${HepMC3_FOUND}>:src/GeneratorHepMCParam.cxx>
                        $<$<BOOL:${HepMC3_FOUND}>:src/AODToHepMC.cxx>
                PUBLIC_LINK_LIBRARIES FairRoot::Base O2::SimConfig O2::CommonUtils O2::DetectorsBase O2::ZDCBase
-                                     O2::SimulationDataFormat ${pythia6Target} ${pythiaTarget} ${hepmcTarget}
+                                     O2::SimulationDataFormat ${pythiaTarget} ${hepmcTarget}
                                      FairRoot::Gen
                TARGETVARNAME targetName)
 
-if(pythia6_FOUND)
-  target_compile_definitions(${targetName} PUBLIC GENERATORS_WITH_PYTHIA6)
-endif()
-
 if(pythia_FOUND)
   target_compile_definitions(${targetName} PUBLIC GENERATORS_WITH_PYTHIA8)
 endif()
@@ -92,11 +82,6 @@ set(headers
     include/Generators/GeneratorService.h
     )
 
-if (pythia6_FOUND)
-   list(APPEND headers include/Generators/GeneratorPythia6.h
-                       include/Generators/GeneratorPythia6Param.h)
-endif()
-
 if(pythia_FOUND)
   list(APPEND headers
               include/Generators/GeneratorPythia8.h
@@ -116,11 +101,6 @@ o2_target_root_dictionary(Generators HEADERS ${headers})
 o2_add_test_root_macro(share/external/extgen.C
                        PUBLIC_LINK_LIBRARIES O2::Generators FairRoot::Base
                        LABELS generators COMPILE_ONLY)
-if(pythia6_FOUND)
-  o2_add_test_root_macro(share/external/pythia6.C
-                         PUBLIC_LINK_LIBRARIES O2::Generators
-                         LABELS generators COMPILE_ONLY)
-endif()
 
 if(doBuildSimulation)
   o2_add_test_root_macro(share/external/QEDLoader.C

Generators/CMakeLists.txt

@@ -7,7 +7,6 @@
 
 #include "Generators/Trigger.h"
 #include "Pythia8/Pythia.h"
-#include "TPythia6.h"
 #include <fairlogger/Logger.h>
 
 o2::eventgen::DeepTrigger
@@ -18,9 +17,6 @@ o2::eventgen::DeepTrigger
     if (!name.compare("pythia8")) {
       auto py8 = reinterpret_cast<Pythia8::Pythia*>(interface);
       nMPI = py8->info.nMPI();
-    } else if (!name.compare("pythia6")) {
-      auto py6 = reinterpret_cast<TPythia6*>(interface);
-      nMPI = py6->GetMSTI(31);
     } else
       LOG(fatal) << "Cannot define MPI for generator interface \'" << name << "\'";
     return nMPI >= mpiMin;